The rotary encoder wheel is a funky user interface element is reminiscent of the original clicking scroll wheel interface on the first iPods.

Use your microcontroller's button and rotary encoder library/hardware support to interface with the pins.

You'll need 7 GPIO total: 5 buttons and 2 rotary encoder pins. There are also two COMmon pins, which you can set to ground or VCC - usually ground so that you can use the microcontroller internal pull-ups for the button/encoders. Note to make our wiring simple, our example code uses GPIO to the COM's and then sets them to outputs, but you can just wire them directly.